Method for Determining Residual Carbamate Compounds on an Elastomeric Article

Abstract

A method and process for determining the propensity of elastomeric articles to discolor or stain is provided. The elastomeric articles tested are generally crosslinked elastomeric articles containing accelerators, such as carbamates. Residual carbamates can cause staining when contacted with metal ions, such as copper. Tests are disclosed for determining the propensity of the elastomeric articles to stain or discolor. The process can include remediation steps for preventing future articles from staining.

1 . A method for determining residual carbamate compounds in elastomeric articles comprising:
 contacting an elastomeric article or an extract obtained from the elastomeric article with a transition metal solution, wherein the transition metal solution is a copper acetate solution, wherein the copper acetate solution comprises a ratio of 5 mg copper acetate per 1 mL of acetone; and   testing the elastomeric article or the extract and transition metal solution for the propensity of the elastomeric article to stain.   
     
     
         2 . A method as defined in  claim 1 , wherein the elastomeric article is tested for staining by a visual observation test for discoloration. 
     
     
         3 . A method as defined in  claim 2 , wherein the discoloration is a yellow discoloration. 
     
     
         4 . (canceled) 
     
     
         5 . A method as defined in  claim 1 , wherein the copper acetate solution is sprayed onto a surface of the elastomeric article. 
     
     
         6 . A method as defined in  claim 1 , wherein the elastomeric article is dipped into the transition metal solution. 
     
     
         7 . A method as defined in  claim 1 , wherein the elastomeric article is a glove. 
     
     
         8 . A method as defined in  claim 1 , wherein the elastomeric article is made from a nitrile polymer. 
     
     
         9 . A method as defined in  claim 1 , wherein the transition metal solution is contacted with an extract obtained from the elastomeric article, the extract being collected by contacting the elastomeric article with an acetone solution. 
     
     
         10 . A method as defined in  claim 9 , wherein the elastomeric article is tested for staining by measuring an absorbance of the extract and transition metal solution at a wavelength using spectrophotometry. 
     
     
         11 . A method as defined in  claim 10 , wherein the absorbance of the extract and transition metal solution is measured at a wavelength of from about 200 nm to about 700 nm. 
     
     
         12 . A method as defined in  claim 10 , wherein the absorbance of the extract and transition metal solution is measured at a wavelength of 433 nm. 
     
     
         13 . A method as defined in  claim 10 , wherein the absorbance measured of the extract and transition metal solution is compared with reference data in order to determine a concentration of carbamate on the elastomeric article. 
     
     
         14 . A method as defined in  claim 13 , wherein the reference data comprises a relationship between absorbance at the measured wavelength and concentration of carbamate. 
     
     
         15 . A method as defined in  claim 14 , wherein the carbamate concentration is zinc diethyldithiocarbamate concentration. 
     
     
         16 . A method as defined in  claim 14 , wherein the carbamate concentration is zinc dibutyldithiocarbamate concentration. 
     
     
         17 . A method as defined in  claim 14 , wherein the carbamate concentration is a mixture of zinc diethyldithiocarbamate and zinc dibutyldithiocarbamate concentration. 
     
     
         18 . A method as defined in  claim 14 , wherein the relationship includes carbamate concentrations of from 0 ppm to about 100 ppm. 
     
     
         19 . A method as defined in  claim 14 , wherein a carbamate concentration of greater than about 0.5 ppm is a positive test for staining. 
     
     
         20 . (canceled) 
     
     
         21 . A method for determining residual carbamate compounds on elastomeric articles comprising:
 contacting an extract obtained from an elastomeric article with a transition metal solution, wherein the transition metal solution is a copper acetate solution, wherein the copper acetate solution comprises a ratio of 5 mg copper acetate per 1 mL of acetone;   measuring an absorbance of the extract and transition metal solution at a wavelength using spectrophotometry; and   comparing the measured absorbance with reference data in order to determine a concentration of carbamate on the elastomeric article.